'Fankoo mummy' says Elsie quickly, not paying attention.
'THank you' I correct, exaggerating the amount of tongue between my teeth. 'Th, th, th' I repeat.
Elsie brings her lip under her top teeth. 'Fffffffff' she says. 'Fffffffank you.'
I try again. 'Stick your tongue out.' Elsie obliges. 'Now trap it between your teeth. Th, th, th...'
Elsie gives it a go, but once she starts to think about the word and not her tongue in a strange place in her mouth, her old habit creeps back. 'Fank you!'
'Try again Elsie, tongue between your teeth.' I encourage. She's done it before, why has she forgotten?
Elsie is bored with this exercise, and suddenly an idea strikes.
'Dziekuje!' she says brightly, her eyes shining with her brilliance.